Fire-derived organic matter (charcoal-like) is considered to be one of the most persistent groups of compounds in all ecosystems. A large part of it resides in soils for centuries to millennia.

Up to now, no systematic inventory has estimated the amount of fire-derived organic matter in soils. This publication reports on a large database established through literature research, and demonstrates that fire-derived organic matter makes up about 50% of the organic compounds currently analytically identifiable in soils. Furthermore, soil properties, such as pH or clay content appear to explain fire-derived organic matter content better than more obvious parameters including fire characteristics, vegetation cover or climate.